Shiva Purana
हविषे सस्यसम्पत्तिर्वृष्टिः सस्याभिवृद्धये ॥ वृष्टेरेव हविस्तस्मादग्नीषोमधृतं जगत् ॥ ८ ॥
The luxuriant growth of Vegetation is for the Havis. The rain contributes to the flourishing growth of vegetation. So Havis is the outcome of rain, the universe is sustained by Agnīṣoma.
english translation
haviSe sasyasampattirvRSTiH sasyAbhivRddhaye ॥ vRSTereva havistasmAdagnISomadhRtaM jagat ॥ 8 ॥
hk transliteration by Sanscript